/* Modern Clean CSS for Shenlong Network (shenlong.cfd) */
:root {
  --primary: #3b82f6;
  --primary-hover: #1d4ed8;
  --primary-light: #eff6ff;
  --text-dark: #0f172a;
  --text-muted: #475569;
  --text-light: #94a3b8;
  --bg-body: #ffffff;
  --bg-alt: #f8fafc;
  --bg-hero: #edf2ff;
  --card-bg: #ffffff;
  --border-color: #e2e8f0;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.07), 0 2px 4px -1px rgba(0,0,0,0.04);
  --shadow-lg: 0 10px 25px -5px rgba(59,130,246,0.12), 0 8px 10px -6px rgba(0,0,0,0.04);
  --radius: 12px;
  --transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans SC", sans-serif;
  color: var(--text-dark);
  background-color: var(--bg-body);
  line-height: 1.6;
}

body {
  overflow-x: hidden;
}

a {
  color: var(--primary);
  text-decoration: none;
  transition: var(--transition);
}

a:hover {
  color: var(--primary-hover);
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

/* Header & Nav */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border-color);
  height: 72px;
  display: flex;
  align-items: center;
}

.header-nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--primary-hover);
}

.brand img {
  width: 40px;
  height: 40px;
  border-radius: 8px;
  object-fit: cover;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
  list-style: none;
}

.nav-links a {
  color: var(--text-dark);
  font-weight: 500;
  font-size: 0.95rem;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--primary);
}

.nav-buttons {
  display: flex;
  align-items: center;
  gap: 12px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 22px;
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: 8px;
  cursor: pointer;
  transition: var(--transition);
  border: 1px solid transparent;
}

.btn-primary {
  background-color: var(--primary);
  color: #ffffff;
  box-shadow: 0 4px 12px rgba(59, 130, 246, 0.3);
}

.btn-primary:hover {
  background-color: var(--primary-hover);
  color: #ffffff;
  transform: translateY(-1px);
}

.btn-outline {
  background-color: #ffffff;
  color: var(--primary);
  border-color: var(--primary);
}

.btn-outline:hover {
  background-color: var(--primary-light);
  color: var(--primary-hover);
}

.btn-recommend {
  background: linear-gradient(135deg, #10b981 0%, #059669 100%);
  color: #ffffff;
  border: none;
}

.btn-recommend:hover {
  background: linear-gradient(135deg, #059669 0%, #047857 100%);
  color: #ffffff;
}

/* Hero Section */
.hero {
  background-color: var(--bg-hero);
  padding: 80px 0 100px 0;
  position: relative;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
}

.hero-content h1 {
  font-size: 3rem;
  font-weight: 800;
  line-height: 1.2;
  color: #0f172a;
  margin-bottom: 20px;
}

.hero-content p {
  font-size: 1.15rem;
  color: var(--text-muted);
  margin-bottom: 36px;
}

.hero-buttons {
  display: flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}

.hero-image {
  display: flex;
  justify-content: center;
}

.hero-card {
  width: 100%;
  max-width: 460px;
  border-radius: 24px;
  overflow: hidden;
  box-shadow: 0 20px 50px rgba(6, 182, 212, 0.25), 0 10px 20px rgba(15, 23, 42, 0.2);
  background: #0b1329;
  border: 2px solid rgba(6, 182, 212, 0.4);
  transition: var(--transition);
  animation: floatDragon 6s ease-in-out infinite;
}

@keyframes floatDragon {
  0%, 100% {
    transform: translateY(0px);
    box-shadow: 0 20px 50px rgba(6, 182, 212, 0.25);
  }
  50% {
    transform: translateY(-10px);
    box-shadow: 0 30px 60px rgba(6, 182, 212, 0.4);
  }
}

.hero-card:hover {
  transform: translateY(-6px) scale(1.02);
  border-color: rgba(6, 182, 212, 0.8);
}

.hero-card img {
  width: 100%;
  height: auto;
  display: block;
}

/* Section Header */
.section {
  padding: 80px 0;
}

.section-header {
  text-align: center;
  max-width: 700px;
  margin: 0 auto 56px auto;
}

.section-header h2 {
  font-size: 2.25rem;
  font-weight: 700;
  color: var(--text-dark);
  margin-bottom: 12px;
}

.section-header p {
  font-size: 1.05rem;
  color: var(--text-muted);
}

/* Features Grid */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 28px;
}

.feature-card {
  background: var(--card-bg);
  padding: 32px;
  border-radius: var(--radius);
  border: 1px solid var(--border-color);
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
}

.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: rgba(59, 130, 246, 0.3);
}

.feature-icon {
  width: 56px;
  height: 56px;
  border-radius: 12px;
  background-color: var(--primary-light);
  color: var(--primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.75rem;
  margin-bottom: 20px;
}

.feature-card h3 {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--text-dark);
}

.feature-card p {
  color: var(--text-muted);
  font-size: 0.95rem;
}

/* Pricing Grid */
.pricing-section {
  background-color: var(--bg-alt);
}

.pricing-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 28px;
}

.pricing-card {
  background: var(--card-bg);
  padding: 36px 28px;
  border-radius: 16px;
  border: 1px solid var(--border-color);
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  position: relative;
  transition: var(--transition);
}

.pricing-card.featured {
  border: 2px solid var(--primary);
  box-shadow: var(--shadow-lg);
  transform: scale(1.03);
}

.pricing-badge {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--primary);
  color: #fff;
  padding: 4px 16px;
  border-radius: 20px;
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.5px;
}

.pricing-header h3 {
  font-size: 1.35rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.pricing-price {
  font-size: 2.25rem;
  font-weight: 800;
  color: var(--primary);
  margin: 16px 0;
}

.pricing-price span {
  font-size: 0.95rem;
  color: var(--text-muted);
  font-weight: 400;
}

.pricing-features {
  list-style: none;
  margin: 24px 0 32px 0;
  flex-grow: 1;
}

.pricing-features li {
  padding: 8px 0;
  font-size: 0.92rem;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 8px;
}

.pricing-features li::before {
  content: "✓";
  color: var(--primary);
  font-weight: bold;
}

/* Downloads Section */
.downloads-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 24px;
}

.download-card {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  padding: 24px;
  text-align: center;
  transition: var(--transition);
}

.download-card:hover {
  transform: translateY(-3px);
  border-color: var(--primary);
  box-shadow: var(--shadow-md);
}

.download-icon {
  font-size: 2.5rem;
  margin-bottom: 12px;
}

.download-card h4 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 6px;
}

.download-card p {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 16px;
}

/* Articles Section */
.articles-section {
  background-color: var(--bg-alt);
}

.articles-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
  gap: 28px;
}

.article-card {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  transition: var(--transition);
}

.article-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.article-body {
  padding: 24px;
  display: flex;
  flex-direction: column;
  flex-grow: 1;
}

.article-tags {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin-bottom: 12px;
}

.tag {
  background: var(--primary-light);
  color: var(--primary-hover);
  padding: 2px 10px;
  border-radius: 4px;
  font-size: 0.78rem;
  font-weight: 600;
}

.article-card h3 {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 12px;
  line-height: 1.4;
}

.article-card p {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-bottom: 20px;
  flex-grow: 1;
}

/* Testimonials / User Reviews */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 28px;
}

.review-card {
  background: var(--card-bg);
  padding: 28px;
  border-radius: var(--radius);
  border: 1px solid var(--border-color);
  box-shadow: var(--shadow-sm);
}

.review-header {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 16px;
}

.review-avatar {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: linear-gradient(135deg, #3b82f6, #06b6d4);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1.1rem;
}

.review-info h4 {
  font-size: 1rem;
  font-weight: 700;
}

.review-info span {
  font-size: 0.82rem;
  color: var(--text-muted);
}

.review-rating {
  color: #f59e0b;
  margin-bottom: 12px;
  font-size: 1rem;
}

.review-text {
  font-size: 0.92rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* FAQ Accordion */
.faq-section {
  background-color: var(--bg-alt);
}

.faq-list {
  max-width: 800px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.faq-item {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  overflow: hidden;
}

.faq-question {
  width: 100%;
  padding: 20px 24px;
  text-align: left;
  background: none;
  border: none;
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-dark);
  display: flex;
  justify-content: space-between;
  align-items: center;
  cursor: pointer;
}

.faq-answer {
  padding: 0 24px 20px 24px;
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.6;
  display: block;
}

/* Article Detail Page Layout */
.article-page {
  padding: 60px 0 100px 0;
}

.breadcrumb {
  display: flex;
  gap: 8px;
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-bottom: 24px;
}

.article-content {
  max-width: 860px;
  margin: 0 auto;
  background: var(--card-bg);
  padding: 48px;
  border-radius: 16px;
  border: 1px solid var(--border-color);
  box-shadow: var(--shadow-sm);
}

.article-content h1 {
  font-size: 2.2rem;
  font-weight: 800;
  margin-bottom: 16px;
  line-height: 1.3;
}

.article-meta {
  display: flex;
  align-items: center;
  gap: 16px;
  font-size: 0.88rem;
  color: var(--text-muted);
  margin-bottom: 32px;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--border-color);
}

.article-body-text {
  font-size: 1.05rem;
  line-height: 1.8;
  color: #334155;
}

.article-body-text h2 {
  font-size: 1.5rem;
  font-weight: 700;
  margin: 36px 0 16px 0;
  color: var(--text-dark);
}

.article-body-text h3 {
  font-size: 1.25rem;
  font-weight: 700;
  margin: 24px 0 12px 0;
  color: var(--text-dark);
}

.article-body-text p {
  margin-bottom: 18px;
}

.article-body-text ul, .article-body-text ol {
  margin: 16px 0 24px 24px;
}

.article-body-text li {
  margin-bottom: 8px;
}

.cta-box {
  background: linear-gradient(135deg, #eff6ff 0%, #dbeafe 100%);
  border: 1px solid #bfdbfe;
  border-radius: var(--radius);
  padding: 32px;
  margin: 40px 0;
  text-align: center;
}

.cta-box h3 {
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--primary-hover);
  margin-bottom: 10px;
}

.cta-box p {
  font-size: 0.98rem;
  color: var(--text-muted);
  margin-bottom: 20px;
}

/* Footer Section & Core Task 2 PBN Pipeline */
.footer {
  background-color: #0b1120;
  color: #94a3b8;
  padding: 60px 0 30px 0;
  border-top: 1px solid #1e293b;
  text-align: center;
}

.footer-content {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 24px;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 1.2rem;
  font-weight: 700;
  color: #ffffff;
}

.footer-brand img {
  width: 36px;
  height: 36px;
  border-radius: 8px;
}

.footer-links {
  display: flex;
  gap: 24px;
  list-style: none;
  flex-wrap: wrap;
  justify-content: center;
}

.footer-links a {
  color: #94a3b8;
  font-size: 0.9rem;
}

.footer-links a:hover {
  color: #ffffff;
}

/* Core Task 2: PBN Friend Links Section */
.footer-pbn {
  margin-top: 16px;
  padding-top: 20px;
  border-top: 1px solid #1e293b;
  width: 100%;
  max-width: 600px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 20px;
  font-size: 0.82rem;
  color: #64748b;
}

.footer-pbn span {
  color: #475569;
}

.footer-pbn a {
  color: #94a3b8;
  text-decoration: none;
  font-size: 0.82rem;
  transition: color 0.2s ease;
}

.footer-pbn a:hover {
  color: var(--primary);
  text-decoration: underline;
}

.copyright {
  font-size: 0.82rem;
  color: #64748b;
  margin-top: 12px;
}

/* Responsive Rules */
@media (max-width: 992px) {
  .hero-grid {
    grid-template-columns: 1fr;
    text-align: center;
  }
  .hero-content h1 {
    font-size: 2.25rem;
  }
  .hero-buttons {
    justify-content: center;
  }
  .pricing-card.featured {
    transform: none;
  }
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
  }
  .header {
    height: 64px;
  }
  .article-content {
    padding: 24px;
  }
  .hero-content h1 {
    font-size: 1.85rem;
  }
}